How to merge 2 pdf files without loosing their quality?

[nibeditaz]

I’ve done a 139 pages catalogue design in illustrator though client told it would be 80 pages maximum but over the period of time it increased and took 139 pages and for that there are 2 AI files and 2 pdf files, now I’ve 2 important questions and I need the answer badly… please help me…
1st question: My client wants that 2 pdf in one file (merged files) but without loosing its quality… How I can do that?
2nd question: I delivered both AI and both pdf to my client as Delivery but when he wants to print that catalogue the print man ask for this… Below is the requirements for print the catalogue…
#Cause it is sewn thread binding, pls make Front cover+Spine+Back cover onto one PDF. Pls make the spine with 9mm.The flat size of the cover is 429*297mm.
I don’t have any idea what he told or ask for… and how to do that!!

[sydneymorgan]

I’ve done a 139 pages catalogue design in illustrator though client told it would be 80 pages maximum but over the period of time it increased and took 139 pages and for that there are 2 AI files and 2 pdf files, now I’ve 2 important questions and I need the answer badly… please help me…

1st question: My client wants that 2 pdf in one file (merged files) but without loosing its quality… How I can do that?

2nd question: I delivered both AI and both pdf to my client as Delivery but when he wants to print that catalogue the print man ask for this… Below is the requirements for print the catalogue…

#Cause it is sewn thread binding, pls make Front cover+Spine+Back cover onto one PDF. Pls make the spine with 9mm.The flat size of the cover is 429*297mm.

I don’t have any idea what he told or ask for… and how to do that!!

If you need to merge interior PDF files, you can use this site: https://smallpdf.com/merge-pdf

It sounds like he wants a single PDF file with the back cover, spine, and front cover (see below). You’ll need to make it the right dimensions and account for bleed along the edges. If it’s outside your realm of experience, just let him know that and suggest another seller for this last portion of the work.

Pls make the spine with 9mm.The flat size of the cover is 429*297mm.

So, the spine should be 9mm wide. Are 429mm by 297mm the dimensions of the entire cover—front, spine, and back (11x16 inches)? You should get the specific measurements of the front cover itself if you intend to take this on.

[nibeditaz]

Thanks for your suggestion my dear and yes I really never experience this type of printing work so I think better follow your words and suggest another seller for this last portion of the work. I really don’t understand this part. Thanks again.